Air heater



G. BLUEMEL Jan. 31, 1933.

AIR HEATER Filed July 23, 1'931 '-.Y 5 of hollow Patented Jan. 3l; 1933 untreu sifaras4 v1 \'rr; Nr oFFrcE srsmsfmc. or

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CHICAGO, ILLINOIS, ,A CQRPOIBAII'ION` ILLntoIs,l assIGNoB' 'ro Danno' or rumors am l Application' .nica .my as,

A vThis invention relates tolair heaters-of the 'L l' "t 'pe vdescribed inthe application' of Gustave lluemel, Serial No.1- 473,349,11ed'August 6,.y

' 1930,'v which heater fconsistsgof-l aplurality flat elements of large v'area arran ed in .a parallel series and spaced apart so t at lthe airto be heatedamay pass between'the 'elements in contact withthesurfacestheresv of. Each element. isv equipped at its lower.

10 end with aburner and at its upper end withi an outlet for 'ths roducts :of o`rnbustion 1' Combustion takes lp ace in-thelower end of each element. and the 'gasesofcombustionthen travel upwardly,therethrough in sheetp 16A-like form,- wiping" avainatvthc inner, surfaces Y of the walls of the f eating uni'tsandin .this

` manner transferring heat through .the wallsof the units `to theffcurrent's' of air ex'terior thereof. 1. i0 It hasv been lfound that such a heat' trans- .ferring device maybe :improved 'as :to eiliciencyv and uniformity of.v `distribution .of the heat by inclusion, in .each heating unitlthere- I of, of an elementv for the 'absorption of heat .25* in large quantities'and,.themradiation thereof "i to the side walls ofthefunits"fBy'this means i 1x-.it "ispossibleto reduce-.the number .of heat' v 4transfer."'units vrequired for performinga givv en quantity=of1work bv thej constructi on desc'rbed in 4v.the above mentioned -applicatlon to increase the eiciencylfofthe `type of `air heaters to lwhic'h'this im'e'nton relates and to provide-therein for more eyen transmission and distribution -ofa large axnount of the heat by radiation.

The object ofthe invention is accomplished ..46 by means of a construction illustratedin the drawing" wherein:

e Figure 1 is a front view of the air' heater, with the casing partly broken away and shown in section, Aand* l.the heat elements and their 45 supports also` shown in section, as indicated by the 1in@ ifeiof Fig. 2.

Figr 2 a longitudinal sectional'view oi' heater. j 1 'Fig'. Bisa' plan viewof some of the heating '1g-150 elements, one `.of said Aelements being shown 1in the 1931. sensing. tragos. W.

in section, .and the-casing is in section,`na f misten-interesan eaukefha described',

" cldes a plurality ofyfiat, hllowkelementsjin? parallel lrelati on and' spaced ."apartf: with-in; 'ai casing. or conduit Vfor. vvthezair. beheated.;

which flowsl upwardly between these elements'.A

- Each heating, element; {isf'form'ed to" provide combustion, and` v'a'tjits' -upper'end with iitgnlot' f let .flue comninicatin' l with astack@ Heat'istransmitte `to the wallsI of eac.

uni-t' 'by convection currents fof :off combustion? .and is `cmducted through the walls'toradiatingfins iover which'theair to be heated isdra'wn or blown by an air blower. The present l`.construction differs ffrom' the former by providing each unit with an additional'heat absorbing and'radiating?` 'element The hot l up their heat tothe center the outer walls of the unit bothby the usual convection currents and by radiation from the central plate.

Referringto the drawing the construction illustrated includesa casing '1 supported by feet .2' and having *atv its` .lower end trans`.

verse horizontally` disposed .channel bars 3, upon which are supported heatingelem'ents 4.

and spaced apart suiciently -to providel space .for the Vupwardtravel of air to be heated along the outer walls of the units to the inlets 5 ofablower 6 mountedwithn the upper-end of casing 1. The blower is driven y a motor 7 supported upon abracket 8, and coupled at 9`to the blower shaft 10. Bearings V11 for the latter are'carried by casing The heating units to which the present invention particularly relates are for'conven- These arearr'anged 'in parallel relation4 ience in casting each formed with a pair of exterorly ribbed side plates 12, the marginal surfaces of which are ianged inwardly, to provide for the top, bottom and end walls of each unit.

These marginal flanges 13 meet at the dividing lines 14 and the two sections of each heat element are clamped together by bolts 15 passing through the projecting ears 16, on each half of a unit. The side walls 17 of each unit are formed to be farther apart at the lower end 18 thereof to provide a coinbustion space 19 in which may be located a gas burner 20.

The gas burner extends through an opening 21 for air left in the bottom of each unit. Each unit is also provided with an opening 22 at its upper end which serves as an outlet to a stack for the products'of combustion. Each outlet 22 is preferably surrounded by flanges 23 extending from the heater units and to which may be attached flues leading toa stack. The walls of each unit at the upper end thereof are preferably rounded outwardly suitable carrying capacity of the gases'of combustion to the outlets 24.

Heat absorbing and radiating lates 25 extend parallel to the side walls 117) of each unit and centrally therebetween. These elements are in the form of heavy metallic lates of suitable material for withstanding t e effects of heat and the action of the gases of combustion, and are conveniently suspended in this location by transverse pins 26 passing therethrough and restin upon the shoulders 27, on the innerl sur aces of the side walls of the heating units.

In the operation of this heater, the air to be heated is drawn upwardly between the units and between the fins 28 thereof, by the blower 6. The heat from the burning gas from the burner 20 in each unit` 'is transmitted to the walls 17 of each heater unit by direct Contact of flame and gases of combustion, and the radiating plate 25 is also heated in this manner and transmits its heat by radiation to the walls 17, by which it is conducted to the outer surfaces thereof and to the ribs 28 over which the air to be heated passes. The plates 25 serve to largely increase the efficiency of this heater, enabling a reduction in the number of heating elements for any required delivery of heat, with reference to this device when not equipped with the heat radiating plates 25.

It is also found that these plates serve to more uniformly distribute the heat throughout the apparatus.

The dimensions of each heater unit and the plate 25 therein are such as to provide passageways for the gases of combustion of considerable width and length, with reference to the extent of separation between the sides of as indicated at 24, to provide said plates and the side walls 17 of the heater units.

It is to be understood that details of the construction shown ma be varied without departing from the spirit of this invention as defined by the following claim.

I claim:

In a heat interchan er, a heat transferring unit consisting o a walled structure having parallel side walls of large area with reference to marginalend connecting walls, a heat absorbing and radiating plate hung in said structure to extend between and parallel with said side walls but slightly s aced therefrom, said walled structure liein formed to provide an inlet at one end anc an outlet at the other end, and means for supplying heat to the inlet end of said structure.

Signed at Chicago this 18th day 0f July,

GUSTAVE BLUEMEL. 

